Alert archive / Texas / Severe Thunderstorm Watches in 2011
Severe Thunderstorm Watch 138
The Storm Prediction Center issued this severe thunderstorm watch at Apr 14, 2011, 11:24 PM CDT for 5 parishes in Louisiana; 13 counties in Texas. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 14, 2011, 11:24 PM CDT (04:24 UTC)
- Expired
- Apr 15, 2011, 2:34 AM CDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
Counties Bossier Parish, LA, Caddo Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, Webster Parish, LA, Camp County, TX, Cass County, TX, Cherokee County, TX, Gregg County, TX, Harrison County, TX, Marion County, TX, Nacogdoches County, TX, Panola County, TX, Rusk County, TX, Shelby County, TX, Smith County, TX, Upshur County, TX, Wood County, TX
The radar
The Shreveport radar (KSHV), 89 km from the middle of the area, began a volume at 04:25 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 20%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 50%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
8 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 14, 11:34 PM CDT | Severe Thunderstorm Warning | SHV | Bowie, Camp, Franklin, Morris, Red River, Titus | 56 min |
| Apr 15, 12:06 AM CDT | Severe Thunderstorm Warning | SHV | Camp, Gregg, Smith, Upshur, Wood | 54 min |
| Apr 15, 12:30 AM CDT | Severe Thunderstorm Warning | SHV | Caddo | 60 min |
| Apr 15, 12:59 AM CDT | Severe Thunderstorm Warning | SHV | Camp, Franklin, Gregg, Harrison, Marion, Smith and 3 more | 61 min |
| Apr 15, 1:14 AM CDT | Severe Thunderstorm Warning | SHV | Bowie, Cass | 61 min |
| Apr 15, 1:35 AM CDT | Severe Thunderstorm Warning | SHV | Caddo | 40 min |
| Apr 15, 2:01 AM CDT | Severe Thunderstorm Warning | SHV | Cherokee, Nacogdoches, Panola, Rusk, Smith | 48 min |
| Apr 15, 2:07 AM CDT | Severe Thunderstorm Warning | SHV | Bossier, Caddo, Webster | 53 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Shreveport, LA (KSHV), launched 00:00Z, 4.4 hours before the alert went out and 97 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 1201 J/kg
- Mixed-layer CIN
- -8 J/kg
- Mixed-layer LCL
- 1314 m above ground
- 0-6 km bulk shear
- 54 kt
- 0-1 km storm-relative helicity
- 117 m²/s²
- 0-3 km storm-relative helicity
- 135 m²/s²
- Significant tornado parameter
- 0.8
- Supercell composite
- 6.5
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 14, 11:56 PM CDT | Mesoscale Discussion | SPC | Bossier, Caddo, De Soto, Webster | 94 min |
| Apr 15, 1:27 AM CDT | Mesoscale Discussion | SPC | Bienville, Bossier, Claiborne, East Carroll, Jackson, Lincoln and 5 more | 93 min |
| Apr 15, 2:19 AM CDT | Tornado Watch | SPC | Bienville, Bossier, Caddo, Caldwell, Catahoula, Claiborne and 20 more | 8 hr |
| Apr 15, 4:21 AM CDT | Mesoscale Discussion | SPC | Caldwell, Catahoula, Concordia, East Carroll, Franklin, Grant and 6 more | 84 min |
| Apr 15, 7:32 AM CDT | Tornado Watch | SPC | Avoyelles, Caldwell, Catahoula, Concordia, East Carroll, Franklin and 8 more | 7 hr |
| Apr 15, 10:28 AM CDT | Mesoscale Discussion | SPC | Caldwell, Catahoula, Concordia, East Carroll, Franklin, LaSalle and 4 more | 2 hr |
| Apr 15, 1:30 PM CDT | Mesoscale Discussion | SPC | Avoyelles, Catahoula, Concordia, East Baton Rouge, East Feliciana, Pointe Coupee and 6 more | 2 hr |
| Apr 15, 2:41 PM CDT | Tornado Watch | SPC | Acadia, Ascension, Assumption, Avoyelles, Concordia, East Baton Rouge and 19 more | 7 hr |
| Apr 15, 3:35 PM CDT | Mesoscale Discussion | SPC | Acadia, Ascension, Avoyelles, Concordia, East Baton Rouge, East Feliciana and 15 more | 85 min |
| Apr 15, 6:09 PM CDT | Mesoscale Discussion | SPC | Ascension, Assumption, East Baton Rouge, East Feliciana, Iberia, Iberville and 12 more | 96 min |
| Apr 14, 8:36 PM CDT | Mesoscale Discussion | SPC | Lamar | 84 min |
| Apr 14, 9:06 PM CDT | Tornado Watch | SPC | Bowie, Cooke, Delta, Fannin, Franklin, Grayson and 4 more | 6 hr |
| Apr 14, 9:59 PM CDT | Mesoscale Discussion | SPC | Collin, Dallas, Denton, Hopkins, Hunt, Rockwall | 31 min |
| Apr 14, 10:04 PM CDT | Severe Thunderstorm Watch | SPC | Anderson, Bell, Collin, Coryell, Dallas, Denton and 19 more | 4 hr |
| Apr 14, 11:11 PM CDT | Mesoscale Discussion | SPC | Bowie, Delta, Fannin, Lamar, Red River, Titus | 94 min |
Nearby
Severe Thunderstorm Watches in Texas, 2011Severe Thunderstorm Watches in Louisiana, 2011Every severe thunderstorm watch in 2011
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.